Since late May, pictures of Hezbollah militants standing amid the ruins of al-Qusayr, the former Syrian rebel stronghold, have offered dramatic evidence of the extent to which foreign Shia fighters are shifting the course of the Syrian war. To many observers, the Lebanese militia’s entry into the conflict has shown definitively that it has been a sectarian war from the outset. According to this view, Syria’s Alawite sect, to which the Assad clan and its security forces belong, is “quasi Shiite,” a fact which accounts for the government’s alliances to Iran and Hezbollah; while Syrian rebel forces are overwhelmingly dominated by the country’s aggrieved Sunni majority, now backed by the Sunni governments of Saudi Arabia, Qatar, and Turkey, along with various foreign Sunni jihadis.

But Bashar al-Assad is head of an ostensibly secular Baathist regime and many Shia think that Alawites are heretics. Why exactly is Hezbollah getting involved, and is this conflict really rooted in religion? The answer to both these questions may lie in a suburb of Damascus called Sayyida Zainab, the site of an important Shia shrine and since the 1970s a haven for foreign Shia activists and migrants in Syria. Today, Hezbollah forces, along with Iraqi Shia fighters, defend the suburb. Though the story of Sayyida Zainab is little known in the West, it may help explain why what began as a peaceful uprising against secular authoritarian rule in 2011 has increasingly become a war between Shia and Sunni that has engulfed much of the surrounding region.

Sayyida Zainab—located some six miles to the southeast of central Damascus—is named after the daughter of the first Shia Imam, Ali Ibn Abi Talib. While Zainab is allegedly buried there (Sunnis believe she is buried in the large Sayyida Zainab mosque in Cairo), the site is less important in the Shia tradition than the shrines in Iraq and Iran. In fact Sayyida Zainab only became a site of mass pilgrimage in the 1980s and 1990s, when a large shrine was built around the tomb with Iranian support.

By the time I did fieldwork there in 2008, however, the suburb of around 150,000 people had become a meeting ground for Shia from around the world. During the summer months, the foreign Shia population would reach tens of thousands, with up to one million pilgrims visiting Sayyida Zainab every year. There were clerics and students from the Gulf, Lebanon, Iraq, Iran, Afghanistan, Africa, and South-East Asia, among other places. Publishers of cultural and religious magazines from Iraq and the Arabian Peninsula were having late-night discussions in the bookshops opposite the shrine. Young religious students were sitting in the Hawza Zainabiyya, a large center for Shia religious study there, or in one of the other smaller religious schools reading and discussing with their mentors. Iranian pilgrims could pay with Iranian currency, their thousand-tuman notes with the iconic picture of Khomeini bundled in the hands of the street vendors.

It was a world apart from the coffee houses and government buildings of central Damascus, where the old rhetoric of secular Arab nationalism still dominated, and at the time, I found it difficult to fathom the government’s reasons for allowing a suburb full of foreign religious students and clerics to flourish. Most Syrians I met had never been to Sayyida Zainab, and whenever I told people I was going there, they advised me not to go, complaining about the Iranians and Iraqis living there and arguing that it didn’t belong to the Syria they knew. Only after the Syrian uprising began in 2011 did it become clear to me that Sayyida Zainab was a crucial part of the alliance with Iran and Arab Shia militias that has until now allowed the Assad regime to keep the upper hand in the civil war.

In fact, the Syrian government had first discovered the strategic value of Sayyida Zainab back in the 1970s. When Hafez al-Assad, the father of Bashar al-Assad, became president in 1971, he was concerned about the legitimacy of his Alawite sect within Islam. While some Sunni scholars had issued fatwas recognizing the Alawites as Muslims, many senior Shia and Sunni clerics refused to do so. Moreover, the Syrian constitution required the president to be a Muslim, and the country’s Sunnis, who make up just over 70 percent of the population, had become increasingly hostile toward the Alawites, who account for only some 10 percent. (The country also includes sizable populations of Christians and Kurds.) Hafez al-Assad found two Shia religious leaders, Musa al-Sadr, the Iranian-Lebanese cleric, and Hasan al-Shirazi, a descendant of a major Iraqi Shia religious family, who were willing to bestow recognition on the Alawite sect in exchange for Syrian patronage. Al-Sadr was given Syrian backing for the Amal Movement in Lebanon, the Shia Islamist organization he had founded; while al-Shirazi, whose political movement had come under severe repression by the Baathist regime in Baghdad, was offered a safe haven for his followers in Syria.

In 1975, al-Shirazi established the Hawza Zainabbiya, the first Shia institution of learning in Sayyida Zainab. At that time Sayyida Zainab was still a small suburb of Damascus and the tomb of Zainab did not yet function as a major site of religious pilgrimage. But the religious school, the Hawza Zainabiyya, grew over time and the importance of the suburb for the Shirazi movement increased after the Shirazis, many of whom had moved to Iran after the Iranian Revolution, fell out with the Iranians around 1983. Scores of Shirazis from all over the region, particularly the movement’s adherents in Saudi Arabia and Bahrain, resettled in Sayyida Zainab.

It was around this time that Syria began to forge links with Hezbollah, which had been created during the Lebanese Civil War by Lebanese Shia and a number of Iranian Revolutionary Guards to counter the Israeli presence in Lebanon. Since resistance to Israel was part of how the Assad regime maintained legitimacy, and Iranian assistance to Hezbollah had to flow through Syria, Hezbollah became a natural partner for Damascus. (Although, in the mid- to late 1980s, Syrian forces in Lebanon also sided with the Amal movement against Hezbollah, reflecting the shifting nature of alliances during the Lebanese war.)

Meanwhile, other senior Shia clerics such as Ali Khamenei, the Supreme Leader of Iran, Muhammad Hussayn Fadlallah, the late Lebanese Grand Ayatollah, and Iraqi Ayatollah Muhammad Taqi al-Mudarrisi established schools and offices in Sayyida Zeinab, and the Damascus suburb became an attractive destination for Shia from across the Middle East who could not go to the Iraqi shrines in Najaf or Kerbala, and who did not want to come under the influence of the Iranian government in Qum—the three most famous centers of Shia religious learning. In addition, thousands of Iraqi Shia settled in Sayyida Zainab after the failed Shia uprising in Iraq in 1991.

To Syrian opposition groups such as the Muslim Brotherhood, the foreign religious activity in Sayyida Zainab was proof that the Assad regime was teaming up with Iran and the region’s Shia to convert the Syrian population. While there was probably no truth to the conversion claims, it cannot be ignored that Sayyida Zainab had become a symbol of the Assad regime’s growing strategic alliance with the Shia—an alliance that has now been thrust into view with Hezbollah’s Syrian offensive this spring.

In part, Hezbollah’s deployments—in al-Qusayr and other areas along the Lebanese border—have served to shore up its main area of influence, the Bekaa valley, the predominantly Shia home to Lebanon’s famous wine industry and the center of its hashish cultivation, and to reduce the flow of weapons to Syrian rebel groups. And yet, equally significant may be Hezbollah’s defense of the Sayyida Zainab shrine itself.

The Damascus suburb is strategically located between the airport and the city center, and by holding on to it, the Assad regime has prevented the rebels from fully encircling the capital. But it is now on the frontlines of the conflict, with rebel forces just a few blocks away, and many foreign and Syrian Shia have fled, fearful of growing attacks on the Shia population there. In May, Syrian rebels desecrated another Shia shrine outside of Damascus and exhumed the body of Hujr bin Adi, a historical figure revered by Shia Muslims, and Sunni jihadis have often stated that they want to destroy the shrine of Sayyida Zainab and drive the Shia out of the country.

In recent weeks, the prominent Sunni Arab cleric al-Qaradawi, who is seen as the spiritual leader of the Muslim Brotherhood and rose to fame through his show on al-Jazeera, has called upon all able Muslim men to join the fight in Syria against the Assad regime, Hezbollah, and the “heretics.” Al-Qaradawi, who had previously defended Hezbollah because of its fight against Israel, used the involvement of Hezbollah to justify his call upon all Sunnis to fight in Syria. He even called Hezbollah, whose name means the “Party of God,” Hizb al-Shaytan, the “Party of the Devil.”

Along with Lebanese Hezbollah, the fight for Sayyida Zainab has drawn a large number of Iraqi Shia fighters to Syria. The Iraqi recruits usually come from one of the Shia militias—including a splinter group of the Sadrists—that became notorious in the Iraqi civil war and in the fight against coalition troops in Iraq. Early on in the conflict a Shia militia, named the Abu Fadl al-Abbas brigade, was also formed to defend the shrine, and allegedly includes Syrian, Lebanese, and Iraqi members, as well as Iranian special forces. These foreign militias might have saved Sayyida Zainab for now, but they have helped turn the Syrian civil war even further into an international conflict. And by choosing to protect a Shia shrine city they have made a sectarian statement, giving support to their enemies’s claims that this is indeed a holy war.

Not all Lebanese Shia leaders think it is smart that Hezbollah is tethering itself so closely to the Assad regime. Senior clerics like Hani Fahs and Ali al-Amin have called for a disassociation from the Syrian civil war. Al-Amin has even stated that “Sayyida Zainab does not want bloodshed in the name of defending her shrine, but rather unity and shunning sedition.” And although the most popular Iraqi Shia Grand Ayatollah, Ali al-Sistani, has not spoken out on this issue, he has told visitors that he is worried about non-Syrian Shia going to fight in Syria, as it might endanger the situation of the Shia in the whole region. Even in Iran, some reformists have criticized Iran’s support for the Assad regime and argue that Iran’s involvement will lead to a sectarian war. But these opinions are often suppressed.

There are also religious leaders in the Gulf who refuse to see the conflict in a purely sectarian light. Ironically, these include revolutionaries who stand accused by their own governments of having incited sectarian hatred. The Saudi Shia cleric Nimr al-Nimr, for example, who is currently on trial in Saudi Arabia for calling for the downfall of the Saudi ruling family, has said the same about Assad, even though he himself was given refuge in Syria and taught in a religious school in Sayyida Zainab in the late 1980s.

But many other Gulf Shia support the defense of the shrine, not least because they spent their summer holidays there or have been involved in the transnational networks that moved through the suburb. Kuwaiti Shia investors, as well as Iranians, own hotels near the shrine, and many Gulf Shia own apartments there. Some of the foreign Shia fighters who travel to Syria might also be motivated by strong religious feelings about Zainab, or by a sense of religious duty to wage jihad against Sunni extremists. Lebanese and Iraqi Shia fighters who have already died in Syria are lauded at home as “martyrs in the defense of the holy shrines of Sayyida Zainab,” even if they were killed elsewhere in the conflict. The Shia fighters have started to resemble their Sunni compatriots, who travel to Syria to fight the “infidel” Assad regime.

It might be tempting to view Shia fighters traveling to a foreign country to defend a religious shrine as the final realization of an age-old battle that started with the schism of Islam after the death of the Prophet Muhammad. Such a simplistic reading is, however, deeply misleading. Sayyida Zainab—a shrine whose status as a site of Shia religious pilgrimage was largely created in the 1980s and 1990s—lies at the heart of a strategic relationship between the Assad regime, Iran, and Arab Shia groups. This relationship uses religious symbols and sectarian language but it is driven far more by geo-strategic interests than faith. The various groups that profit from a further sectarianization of the conflict, this time on the Shia side, are to blame. These include Iran, which is trying to re-establish its influence over all Shia political movements and groups, whether in the Gulf, in Iraq or elsewhere.

This is not a fight purely or even primarily about Islam; it is a war about the future of the Middle East. Unfortunately, however, all the talk about sectarian war is fast becoming a self-fulfilling prophecy. And by misunderstanding the complicated history of Syria’s alliances with Shia groups, we may contribute to the very sectarian tensions that are tearing the region apart.

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